Efficient photochemical lysis is *possible", but not the way to bet. If it happens, it will enter the mix. There is no reason to think it would involve less use

Efficient photochemical lysis is *possible", but not the way to bet. If it happens, it will enter the mix. There is no reason to think it would involve less use of metals than photovoltaics. Until hydrocarbon burning is a negligible part of energy production, a kWh of solar exactly displaces the equivalent amount of CO2 production. It is for now the most cost-effective way to keep CO2 from entering the atmosphere, much more so than any extractive process could match, and getting cheaper by the day. When we are producing much less CO2, we will need to start collecting and sequestering carbon. Turning it into fuel again, by whatever means, just cycles it back to the atmosphere when the fuel is burned. Probably the main method of capturing existing CO2 for sequestration will be geochemical.